1. Field of the Invention
This invention relates to portable optical scanners for reading indicia of varying light reflectivity, and in particular to such scanners which are adapted to be worn on the person. The invention further relates to optical scanning systems in which the optical module for generating and emitting the light beam is physically separate and apart from the detector module. The invention also relates to a laser pointer, adapted to be worn on a finger of a user.
2. Description of the Related Art
Various optical readers and optical scanning systems have been developed heretofore for reading indicia such as bar code symbols appearing on the label or on the surface of an article. The symbol itself is a coded pattern of indicia comprised of, for example, a series of bars of various widths spaced apart from one another so bound spaces of various widths, the bars and spaces having different light reflecting characteristics. The readers in scanning systems electro-optically transform the graphic indicia into electrical signals, which are decoded into alphanumeric characters that are intended to be descriptive of the article or some characteristic thereof. Such characteristics are typically represented in digital form and utilized as an input to a data processing system for applications in point-of-sale processing, inventory control and the like. Scanning systems of this general type have been disclosed, for example, in U.S. Pat. Nos. 4,251,798; 4,369,361; 4,387,297; 4,409,470; 4,760,248; 4,896,026, all of which have been assigned to the same assignee as the instant application. As disclosed in the above patents, one embodiment of such scanning systems includes, inter alia, a hand held, portable laser scanning device supported by a user, which is configured to allow the user to aim the scanning head of the device, and more particularly, a light beam, at a targeted symbol to be read.
Such prior art hand held devices generally incorporate a light-receiving module which receives the light that has been reflected from the bar code symbol and determines, from the reflected pattern, the sequences of bars and spaces within the symbol. The unit may also incorporate decoding circuitry to decode the received information and to recover the underlying data (for example the alphanumeric data) which the bar code symbol represents.
It may in some circumstances be disadvantageous for the light generating and emitting module to be housed within the same unit as the light-receiving module and the decoding circuitry. In the first place, locating everything within the main housing requires that the bar code to be read is positioned so that most or at least a substantial proportion of the reflected light returns to the unit along the same path as the emitted light. It might not always be convenient for a user to position the bar code reading and/or the bar code so that the light is reflected back along the same path in that way. Secondly, locating everything within the same unit means that the unit has to be physically rather large and relatively heavy. Users may not find it easy to operate for long periods.
In the field of laser pointers, it is known to provide small hand held units which users can use at conferences, seminars or the like for pointing purposes. The visible spot of the laser beam, when shone onto a screen, indicates to the audience the point of interest, and enables the lecturer to dispense with the traditional physical pointer. Although modern laser pointers are relatively small and compact, they nevertheless still have to be grasped in the hand of the lecturer, which naturally restricts the lecturer""s user of that particular hand. Typically, the laser pointer has to be put down every time the lecturer wishes to do something else, such as to turn over a page in his or her notes, or to operate and overhead projector.
It is a general object of the present invention at least to alleviate some of these problems of the prior art.
It is a further object to provide a portable optical scanning system with improved ergonomics, and which will be easier for a user to operate for long periods.
It is a further object of the present invention to reduce the weight of a portable optical scanning system adapted to be held in the hand of a user, or mounted to the user""s body.
It is yet a further object to provide a laser pointer which permits the lecturer greater freedom to use his or her hands without continually having to put down and to pick up the pointer.
It is yet a further object to provide an easy to operate and convenient to use laser pointer.
It is yet a further object to provide a laser pointer which can optionally be used as part of a portable scanning system.
Additional objects, advantages and novel features of the present invention will become apparent to those skilled in the art from this disclosure, including the following detail description, as well as by practice of the invention. While the invention is described below with reference to preferred embodiments, it should be understood that the invention is not limited thereto. Those of ordinary skill in the art having access to the teachings herein will recognize additional applications, modifications and embodiments in other fields which are within the scope of the invention as disclosed and claimed herein and with respect to which the invention could be of significant utility.
According to a first aspect of the present invention there is provided an optical system for reading indicia of different light reflectivity comprising:
an optical module having a light emitter for generating and emitting a light beam for illuminating an indicia to be read; and
a first peripheral module, housed separate and apart from said optical module, having a light detector for detecting the reflection of light from said indicia and producing electrical signals responsive to the light received.
The system may, but need not, be a scanning system in which the light beam scans the indicia to be read. Alternatively, the light beam may be merely illuminating; in that case the light detector may preferably be a CCD detector.
In a preferred embodiment, the optical module incorporates or forms part of a ring which is desirably worn on an index finger of the user. To scan the indicia, the user points his or her index finger in the relevant direction. In some embodiments, an automatic scanning mechanism may be incorporated within the module, so that the emitted beam automatically scans back and forth across the indicia (either in a two-dimensional scan or in a one-dimensional scan) even when the module is held stationary. In other embodiments, however, no automatic scanning mechanism is provided, and the emitted light beam emerges in a fixed direction from the module. In those embodiments, the user scans the beam across the indicia to be read by manually moving the module, typically by moving his or her arm back and forth or by a twisting movement of the wrist.
Switching means may be provided for actuating the optical module. Preferably, these may comprise a switch or button, attached to or forming part of the ring or part of a housing secured to the ring, whereby the user can operate the device merely by pressing the button with his or her thumb. This is particularly convenient when the module is arranged to be worn on the index finger. Alternatively, a pull-cord may be provided which is secured to a second ring, arranged to be worn on a finger of the user""s hand adjacent to the finger which is wearing the optical module. By a suitable movement of the fingers, for example by flexing the second finger, the cord is pulled thereby operating the device.
It will of course be understood that there are many other possibilities for actuating the device, including switch mechanisms which operate under voice control, and mechanisms which determine when the user""s hand is being moved in a scanning motion.
The first peripheral module which has a light detector for detecting the reflection of light from the indicia, may be either fixedly mounted to a stationary support or alternatively worn by the user. In a preferred embodiment, the first peripheral module takes the form of a wrist watch (or includes a wrist watch), and is worn on the same hand which wears the optical module. In that way, it is relatively easy to ensure that the detector or detectors face in the right direction to receive the reflected light. Alternatively, however, the first peripheral module could be worn on the other arm, or could be secured elsewhere on the user""s person, for example on a belt.
The first peripheral module may incorporate radio frequency communication means, enabling the module to communicate with either a fixed base unit or, in some embodiments, a second peripheral module. In one preferred arrangement, the second peripheral module may be worn on the user""s other arm. The second peripheral module may also incorporate radio frequency communication means, allowing communication between the second module and the first module, and (preferably at a different frequency) between the second module and a fixed base unit.
The optical module, the first peripheral module and the second peripheral module are all preferably operated by means of portable batteries, desirably relatively compact batteries which can be located within the respective housings.
In further embodiments, the optical module may be adapted to be held in the hand of a user and may be either gun-shaped or pen-shaped. The optical module could also be mounted to a stationary support.
According to a second aspect of the present invention there is provided a system for reading indicia having parts of different light reflectivity, comprising:
a light emitter for generating a light beam which illuminates the indicia and for producing reflected light of variable intensity reflected from said indicia; said light emitter having a housing adapted to be worn on a single finger of a user in a position such that the light beam is directed in a natural pointing direction of said finger; and
an optical detector for detecting said reflected light and producing an electrical signal indicative of the reflected light intensity; said detector having a housing adapted to be worn by the user in a position spaced apart from the light emitter.
The light emitter preferably generates a beam which scans the indicia.
A stand or container may be provided to receive the first and/or second peripheral modules when they are not in use. In the preferred form, this may comprise a box (akin to a jewellery box) having recesses for receiving the first peripheral unit in the form of a watch, and a second peripheral unit in the form of a ring. The stand/container may include electrical contacts, which are arranged to abut corresponding contacts on the first and/or peripheral modules, thereby allowing a battery of either or both of the modules to be recharged when the system is not in use. The box may have a lid, and may be lockable, to provide security.
Where the first peripheral module includes a data store, readout data contacts may be provided on the stand whereby the data may be downloaded to a computer automatically or on demand.
According to a third aspect of the present invention there is provided a light pointer module comprising:
a ring adapted to be worn on a single finger of a user;
a housing attached to the ring; and
a light emitting means within the housing arranged to generate and emit a light beam, whereby by pointing the finger the user may direct the light beam.
The laser pointer may desirably incorporate a trigger mechanism such as the button mechanism or cord mechanism described above.
To enhance the visible effect of the light beam, the light emitting means preferably comprise a visible laser diode (VLD) whose output passes through a collimating optical system. Electronic control means may be provided which maintain the laser output at a predetermined level.
A battery is preferably provided within the housing.
It is within the scope of the present invention for the laser pointer just described to be used in conjunction with the optical scanning system described above.
According to a fourth aspect of the present invention there is provided a light pointer module comprising: a light pointer module comprising:
a portable housing;
a light emitter within the housing arranged to generate a light beam, whereby by pointing the module a user may direct the light beam;
a scanning element for selectively scanning the light beam;
a user-actuable switch in a first position of which the module emits a steady beam and in a second position of which the scanning element is actuated so that the module emits a scanning beam.
According to a fifth aspect of the present invention there is provided an optical system adapted to be worn on the body of a user, the system comprising: an optical system adapted to be worn on the body of a user, the system comprising:
an optical module having a light emitter for generating and emitting a light beam; and
a band secured to the module and adapted to be worn around a part of the user""s body, the band incorporating a battery for powering the module.
The invention may be carried into practice in a number of ways, and several specific embodiments will now be described, by way of example, with reference to the drawings.